Metastable-particle desorption from Ne-Ar and Ne-Kr solid alloys stimulated by photon excitation were studied using synchrotron radiation as excitation source. Excitation of Ne excitons by optically allowed transitions led mainly to desorption of the other components of the alloy revealing a very efficient energy transfer process. On the other hand, the excitation of the partially allowed electronic transition at the surface (2p(5) 3p) of Ne showed almost no electronic energy transfer to the matrix and desorption of Ne metastables was observed. A sharp enhancement of the Ar metastable signal with respect to pure solid Ar was also observed in the study of Ne-Ar alloys in the energy range below the excitation of Ne excitons. Different mechanisms for desorption are suggested according to the energy region of excitation.